Genome mapping and molecular breeding of tomato.
Genome mapping and molecular breeding of tomato.
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DOI：
10.1155/2007/64358
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发表时间：
2007
期刊：
影响因子：
--
通讯作者：
Foolad MR
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文献类型：
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作者：
Foolad MR
栽培番茄（Lycopersicon esculentum）是全球消费量第二大的蔬菜，也是在遗传学、基因组学和育种方面经过深入研究的农作物品种。它是最早构建遗传连锁图谱的农作物之一，目前有几种基于栽培番茄和各种野生番茄品种之间杂交的分子图谱。该高密度分子图谱是基于 L. esculentum × L. pennellii 杂交开发的，包括 2200 多个标记，平均标记距离小于 1 cM，平均每 cM 750 kbp。不同类型的分子标记如 RFLP、AFLP、SSR、CAPS、RGA、EST 和 COS 已被开发并定位到 12 条番茄染色体上。标记已广泛用于许多生物学和农业重要性状的基因和 QTL 的识别和定位，偶尔也用于种质筛选、指纹识别和标记辅助育种。 MAS 在番茄育种中的应用很大程度上受到栽培品种内有限的标记多态性和经济原因的限制。此外，在使用时，MAS 主要用于改善简单遗传的性状，而很少用于改善复杂的性状。后者是由于缺乏可靠的基于 PCR 的标记以及连锁拖拽问题造成的。人们正在努力开发具有更高分辨率的高通量标记，包括 SNP。不断扩大的番茄 EST 数据库目前包括约 214000 个序列、新的微阵列 DNA 芯片以及正在进行的测序项目预计将有助于开发更实用的标记。已经开发了几个 BAC 文库，有助于基于图谱的基因和 QTL 克隆。番茄基因组常染色质部分的测序为重要基因和 QTL 的比较和功能分析铺平了道路。
The cultivated tomato, Lycopersicon esculentum, is the second most consumed vegetable worldwide and a well-studied crop species in terms of genetics, genomics, and breeding. It is one of the earliest crop plants for which a genetic linkage map was constructed, and currently there are several molecular maps based on crosses between the cultivated and various wild species of tomato. The high-density molecular map, developed based on an L. esculentum × L. pennellii cross, includes more than 2200 markers with an average marker distance of less than 1 cM and an average of 750 kbp per cM. Different types of molecular markers such as RFLPs, AFLPs, SSRs, CAPS, RGAs, ESTs, and COSs have been developed and mapped onto the 12 tomato chromosomes. Markers have been used extensively for identification and mapping of genes and QTLs for many biologically and agriculturally important traits and occasionally for germplasm screening, fingerprinting, and marker-assisted breeding. The utility of MAS in tomato breeding has been restricted largely due to limited marker polymorphism within the cultivated species and economical reasons. Also, when used, MAS has been employed mainly for improving simply-inherited traits and not much for improving complex traits. The latter has been due to unavailability of reliable PCR-based markers and problems with linkage drag. Efforts are being made to develop high-throughput markers with greater resolution, including SNPs. The expanding tomato EST database, which currently includes ∼214 000 sequences, the new microarray DNA chips, and the ongoing sequencing project are expected to aid development of more practical markers. Several BAC libraries have been developed that facilitate map-based cloning of genes and QTLs. Sequencing of the euchromatic portions of the tomato genome is paving the way for comparative and functional analysis of important genes and QTLs.